In a wireless communications network, user equipment may be out of network coverage. For example, users are in places with a weak network signal or places not covered by a network signal, such as a basement, and the user equipment out of network coverage are referred to as remote user equipment. In this case, to enable the remote user equipment out of network coverage to maintain a communication connection to a network, in an implementation manner, as shown in FIG. 1, user equipment that is relatively close to the remote user equipment, that can exchange information with the remote user equipment, and that falls within the network coverage may be used as relay user equipment, and data is forwarded between a user and the network by using the relay user equipment.
Currently, a technical recommendation that user equipment is used as a relay device is already used in communication of emergency services such as a public safety service, to resolve problems of communication of some users out of network coverage.
In the prior art, in a process of establishing a connection between remote user equipment and relay user equipment, after the relay user equipment enables a relay service function, when sending a registration request to an application server for registration, the relay user equipment receives group member information returned by the application server. The relay user equipment may establish, according to the group member information, a connection to user equipment needing a relay service, to provide a relay service for the user equipment.
During implementation of the foregoing process, timing when the relay user equipment receives the group member information is after the relay service function is enabled. If the relay service function is enabled after registration of the relay user equipment is already completed, the relay user equipment cannot provide a relay service. In addition, the relay user equipment can establish a connection to any user equipment. Consequently, security of a relay service function is relatively poor.